United States germanium

In the United States, germanium is obtained as a by-product of zinc production from zinc blende ores. The ore is concentrated by the flotation process. Concentrated ore is then roasted, converting zinc and the impurity metals to their oxides. Heating the crude oxides with sodium chloride and coal converts germanium and other impurity metal oxides into their volatile chlorides. The chloride vapors are condensed and germanium chloride, GeCh, is separated from the condensate by fractional distillation. 

In 1990, the actual world refinery production of germanium was estimated at 76 ton, a decrease of about 7% compared with the 1989 level2 4. This decline is attributed to an oversupply and to a lower level of demand for the metal. The main producers of germanium products are located in the United States, Belgium, France, Germany and Japan. 

Germanium first became important for its use in semiconductors. This application still accounts for about 15 percent of the germanium produced. But other uses of the element are now more important. About 50 percent of the germanium produced in the United States is now used in the manufacture of infrared optics and another 30 percent in fiber optic systems. 

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